1. Field of the Invention
The present invention relates generally to electrical safety equipment and, more particularly, to an improved power system safety monitor for detecting faults in electrical power systems and for generating a command signal to actuate the power system circuit breakers.
2. Description of the Prior Art
In electrical power systems used with mining and other electrical equipment, it is essential that the power lines and ground lines be constantly monitored to prevent electrical faults from occurring in the system. Sparks caused by an electrical fault may result in injury to nearby personnel, ignition of volatile gases, or other accidents. Such accidents may have catastrophic results to personnel and equipment, particularly in underground mines.
Electrical and electronic devices have been developed in the past in an effort to provide a detector for detecting faults in the power system and for deenergizing the system before a hazardous condition can develop. However, such devices typically require a pilot conductor, independent of the other conductors in the power system, which results in additional system complexity and additional cost. U.S. Pat. No. 3,995,200 is representative of prior art.